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| Author | Tysklind, N.; Etienne, M.-P.; Scotti-Saintagne, C.; Tinaut, A.; Casalis, M.; Troispoux, V.; Cazal, S.-O.; Brousseau, L.; Ferry, B.; Scotti, I. | ||||
| Title | Microgeographic local adaptation and ecotype distributions: The role of selective processes on early life-history traits in sympatric, ecologically divergent Symphonia populations | Type | Journal Article | ||
| Year | 2020 | Publication | Ecology and Evolution | Abbreviated Journal | Ecology and Evolution |
| Volume | 10 | Issue | 19 | Pages | 10735-10753 |
| Keywords | determinants of plant community diversity and structure; evolutionary ecology; landscape ecology; local adaptation; Neotropical forest; plant development and life-history traits; reciprocal transplantation experiments; Symphonia | ||||
| Abstract | Trees are characterized by the large number of seeds they produce. Although most of those seeds will never germinate, plenty will. Of those which germinate, many die young, and eventually, only a minute fraction will grow to adult stage and reproduce. Is this just a random process? Do variations in germination and survival at very young stages rely on variations in adaptations to microgeographic heterogeneity? and do these processes matter at all in determining tree species distribution and abundance?. We have studied these questions with the Neotropical Symphonia tree species. In the Guiana shield, Symphonia are represented by at least two sympatric taxa or ecotypes, Symphonia globulifera found almost exclusively in bottomlands, and a yet undescribed more generalist taxon/ecotype, Symphonia sp1. A reciprocal transplantation experiment (510 seeds, 16 conditions) was set up and followed over the course of 6 years to evaluate the survival and performance of individuals from different ecotypes and provenances. Germination, survival, growth, and herbivory showed signs of local adaptation, with some combinations of ecotypes and provenances growing faster and surviving better in their own habitat or provenance region. S. globulifera was strongly penalized when planted outside its home habitat but showed the fastest growth rates when planted in its home habitat, suggesting it is a specialist of a high-risk high-gain strategy. Conversely, S. sp1 behaved as a generalist, performing well in a variety of environments. The differential performance of seeds and seedlings in the different habitats matches the known distribution of both ecotypes, indicating that environmental filtering at the very early stages can be a key determinant of tree species distributions, even at the microgeographic level and among very closely related taxa. Furthermore, such differential performance also contributes to explain, in part, the maintenance of the different Symphonia ecotypes living in intimate sympatry despite occasional gene flow. © 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd | ||||
| Address | UMR AMAP, IRD, Cirad, CNRS, INRAE, Université Montpellier, Montpellier, France | ||||
| Corporate Author | Thesis | ||||
Publisher  |
John Wiley and Sons Ltd | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 20457758 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 951 | ||
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| Author | Perrot, T.; Guillaume, S.; Nadine, A.; Jacques, B.; Philippe, G.; Stéphane, D.; Rodnay, S.; Mélanie, M.-R.; Eric, G. | ||||
| Title | A reverse chemical ecology approach to explore wood natural durability | Type | Journal Article | ||
| Year | 2020 | Publication | Microbial Biotechnology | Abbreviated Journal | Microb. Biotechnol. |
| Volume | 13 | Issue | 5 | Pages | 1673-1677 |
| Keywords | glutathione transferase; Article; biodegradation; data base; detoxification; ecology; enzyme activity; enzyme metabolism; forest; molecular dynamics; physical parameters; species identification; thermal analysis; Trametes versicolor; wood; wood durability | ||||
| Abstract | The natural durability of wood species, defined as their inherent resistance to wood-destroying agents, is a complex phenomenon depending on many biotic and abiotic factors. Besides the presence of recalcitrant polymers, the presence of compounds with antimicrobial properties is known to be important to explain wood durability. Based on the advancement in our understanding of fungal detoxification systems, a reverse chemical ecology approach was proposed to explore wood natural durability using fungal glutathione transferases. A set of six glutathione transferases from the white-rot Trametes versicolor were used as targets to test wood extracts from seventeen French Guiana neotropical species. Fluorescent thermal shift assays quantified interactions between fungal glutathione transferases and these extracts. From these data, a model combining this approach and wood density significantly predicts the wood natural durability of the species tested previously using long-term soil bed tests. Overall, our findings confirm that detoxification systems could be used to explore the chemical environment encountered by wood-decaying fungi and also wood natural durability. © 2020 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology. | ||||
| Address | Université de Lorraine, INRAE, LERMAB, Nancy, France | ||||
| Corporate Author | Thesis | ||||
| Publisher |
John Wiley and Sons Ltd | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 17517907 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 955 | ||
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| Author | Binelli, G.; Montaigne, W.; Sabatier, D.; Scotti-Saintagne, C.; Scotti, I. | ||||
| Title | Discrepancies between genetic and ecological divergence patterns suggest a complex biogeographic history in a Neotropical genus | Type | Journal Article | ||
| Year | 2020 | Publication | Ecology and Evolution | Abbreviated Journal | Ecology and Evolution |
| Volume | 10 | Issue | 11 | Pages | 4726-4738 |
| Keywords | allopatric divergence; Amazon; Guiana Shield; interspecific gene flow; Myristicaceae; secondary contact; Virola | ||||
| Abstract | Phylogenetic patterns and the underlying speciation processes can be deduced from morphological, functional, and ecological patterns of species similarity and divergence. In some cases, though, species retain multiple similarities and remain almost indistinguishable; in other cases, evolutionary convergence can make such patterns misleading; very often in such cases, the “true” picture only emerges from carefully built molecular phylogenies, which may come with major surprises. In addition, closely related species may experience gene flow after divergence, thus potentially blurring species delimitation. By means of advanced inferential methods, we studied molecular divergence between species of the Virola genus (Myristicaceae): widespread Virola michelii and recently described, endemic V. kwatae, using widespread V. surinamensis as a more distantly related outgroup with different ecology and morphology—although with overlapping range. Contrary to expectations, we found that the latter, and not V. michelii, was sister to V. kwatae. Therefore, V. kwatae probably diverged from V. surinamensis through a recent morphological and ecological shift, which brought it close to distantly related V. michelii. Through the modeling of the divergence process, we inferred that gene flow between V. surinamensis and V. kwatae stopped soon after their divergence and resumed later, in a classical secondary contact event which did not erase their ecological and morphological differences. While we cannot exclude that initial divergence occurred in allopatry, current species distribution and the absence of geographical barriers make complete isolation during speciation unlikely. We tentatively conclude that (a) it is possible that divergence occurred in allopatry/parapatry and (b) secondary contact did not suppress divergence. © 2020 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. | ||||
| Address | INRAE, URFM, Avignon, France | ||||
| Corporate Author | Thesis | ||||
| Publisher |
John Wiley and Sons Ltd | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 20457758 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 963 | ||
| Permanent link to this record | |||||
| Author | Servigne, P.; Orivel, J.; Azémar, F.; Carpenter, J.; Dejean, A.; Corbara, B. | ||||
| Title | An uneasy alliance: a nesting association between aggressive ants and equally fierce social wasps | Type | Journal Article | ||
| Year | 2020 | Publication | Insect Science | Abbreviated Journal | Insect Science |
| Volume | 27 | Issue | 1 | Pages | 122-132 |
| Keywords | Azteca chartifex ants; interspecific association; mutualism; Polybia rejecta wasps; scent trail erasure | ||||
| Abstract | Although the Neotropical territorially dominant arboreal ant Azteca chartifex Forel is very aggressive towards any intruder, its populous colonies tolerate the close presence of the fierce polistine wasp Polybia rejecta (F.).
In French Guiana, 83.33% of the 48 P. rejecta nests recorded were found side by side with those of A. chartifex. This nesting association results in mutual protection from predators (i.e., the wasps protected from army ants; the ants protected from birds). We conducted field studies, laboratory-based behavioral experiments and chemical analyses to elucidate the mechanisms allowing the persistence of this association. Due to differences in the cuticular profiles of the two species, we eliminated the possibility of chemical mimicry. Also, analyses of the carton nests did not reveal traces of marking on the envelopes. Because ant forager flows were not perturbed by extracts from the wasps' Dufour's and venom glands, we rejected any hypothetical action of repulsive chemicals. Nevertheless, we noted that the wasps 'scraped' the surface of the upper part of their nest envelope using their mandibles, likely removing the ants' scent trails, and an experiment showed that ant foragers were perturbed by the removal of their scent trails. This leads us to use the term 'erasure hypothesis'. Thus, this nesting association persists thanks to a relative tolerance by the ants towards wasp presence and the behavior of the wasps that allows them to 'contain' their associated ants through the elimination of their scent trails, direct attacks, 'wing-buzzing' behavior and ejecting the ants. |
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| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher |
John Wiley & Sons, Ltd (10.1111) | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1672-9609 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | doi: 10.1111/1744-7917.12597 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 885 | ||
| Permanent link to this record | |||||
| Author | Ziegler, C.; Dusenge, M.E.; Nyirambangutse, B.; Zibera, E.; Wallin, G.; Uddling, J. | ||||
| Title | Contrasting Dependencies of Photosynthetic Capacity on Leaf Nitrogen in Early- and Late-Successional Tropical Montane Tree Species | Type | Journal Article | ||
| Year | 2020 | Publication | Frontiers in Plant Science | Abbreviated Journal | Front. Plant Sci. |
| Volume | 11 | Issue | Pages | 500479 | |
| Keywords | allocation; early successional; late successional; nitrogen; photosynthesis; tropical montane forests | ||||
| Abstract | Differences in photosynthetic capacity among tree species and tree functional types are currently assumed to be largely driven by variation in leaf nutrient content, particularly nitrogen (N). However, recent studies indicate that leaf N content is often a poor predictor of variation in photosynthetic capacity in tropical trees. In this study, we explored the relative importance of area-based total leaf N content (Ntot) and within-leaf N allocation to photosynthetic capacity versus light-harvesting in controlling the variation in photosynthetic capacity (i.e. Vcmax, Jmax) among mature trees of 12 species belonging to either early (ES) or late successional (LS) groups growing in a tropical montane rainforest in Rwanda, Central Africa. Photosynthetic capacity at a common leaf temperature of 25˚C (i.e. maximum rates of Rubisco carboxylation, Vcmax25 and of electron transport, Jmax25) was higher in ES than in LS species (+ 58% and 68% for Vcmax25 and Jmax25, respectively). While Ntot did not significantly differ between successional groups, the photosynthetic dependency on Ntot was markedly different. In ES species, Vcmax25 was strongly and positively related to Ntot but this was not the case in LS species. However, there was no significant trade-off between relative leaf N investments in compounds maximizing photosynthetic capacity versus compounds maximizing light harvesting. Both leaf dark respiration at 25˚C (+ 33%) and, more surprisingly, apparent photosynthetic quantum yield (+ 35%) was higher in ES than in LS species. Moreover, Rd25 was positively related to Ntot for both ES and LS species. Our results imply that efforts to quantify carbon fluxes of tropical montane rainforests would be improved if they considered contrasting within-leaf N allocation and photosynthetic Ntot dependencies between species with different successional strategies. © Copyright © 2020 Ziegler, Dusenge, Nyirambangutse, Zibera, Wallin and Uddling. | ||||
| Address | Department of Biology, The University of Western Ontario, London, ON, Canada | ||||
| Corporate Author | Thesis | ||||
| Publisher |
Frontiers Media S.A. | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1664462x (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 953 | ||
| Permanent link to this record | |||||
| Author | Van Langenhove, L.; Janssens, I.A.; Verryckt, L.; Brechet, L.; Hartley, I.P.; Stahl, C.; Courtois, E.; Urbina, I.; Grau, O.; Sardans, J.; Peguero, G.; Gargallo-Garriga, A.; Peñuelas, J.; Vicca, S. | ||||
| Title | Rapid root assimilation of added phosphorus in a lowland tropical rainforest of French Guiana | Type | Journal Article | ||
| Year | 2020 | Publication | Soil Biology and Biochemistry | Abbreviated Journal | Soil Biol. Biochem. |
| Volume | 140 | Issue | 107646 | Pages | |
| Keywords | Fertilization; Nitrogen; Phosphorus; Plant root simulator probes; Root system; Tropical forest; Nitrogen; Nitrogen fertilizers; Phosphorus; Plants (botany); Soils; Tropics; Fertilization; Mycorrhizal fungus; N and P fertilizer; P availabilities; Plant root simulators; Root system; Tropical forest; Tropical rain forest; Forestry; Fungi | ||||
| Abstract | Tree growth on weathered soils in lowland tropical forests is limited by low phosphorous (P) availability. However, nutrient manupulation experiments do not always increase the P content in these trees, which raises the question whether trees are taking up added P. In French Guianese lowland rainforest, we measured changes in nitrogen (N) and P availability before and up to two months after N and P fertilizer addition, in soils with intact root systems and in soils where roots and mycorrhizal fungi were excluded by root exclusion cylinders. When the root system was excluded, P addition increased P availability to a much greater extent and for a longer time than in soils with an intact root system. Soil N dynamics were unaffected by root presence/absence. These results indicate rapid P uptake, but not N uptake, by tree roots, suggesting a very effective P acquisition process in these lowland rainforests. | ||||
| Address | Global Change Research Institute, Czech Academy of Sciences, Czech Republic | ||||
| Corporate Author | Thesis | ||||
| Publisher |
Elsevier Ltd | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 00380717 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Export Date: 19 November 2019; Coden: Sbioa; Correspondence Address: Van Langenhove, L.; Centre of Excellence PLECO (Plants and Ecosystems), Department of Biology, University of Antwerp, Wilrijk, Belgium; email: leandro.vanlangenhove@uantwerpen.be | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 897 | ||
| Permanent link to this record | |||||
| Author | Do, N.A.; Dias, D.; Zhang, Z.; Huang, X.; Nguyen, T.T.; Pham, V.V.; Nait-Rabah, O. | ||||
| Title | Study on the behavior of squared and sub-rectangular tunnels using the Hyperstatic Reaction Method | Type | Journal Article | ||
| Year | 2020 | Publication | Transportation Geotechnics | Abbreviated Journal | Transp. Geotech. |
| Volume | 22 | Issue | 100321 | Pages | |
| Keywords | Finite element method; Lining; Squared shape; Sub-rectangular shape; Tunnel; efficiency measurement; finite element method; numerical model; transportation development; transportation planning; tunnel design; tunnel lining | ||||
| Abstract | |||||
| Address | Saint-Petersburg Mining University, Russian Federation | ||||
| Corporate Author | Thesis | ||||
| Publisher |
Elsevier Ltd | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 22143912 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 915 | ||
| Permanent link to this record | |||||
| Author | Duplais, C.; Papon, N.; Courdavault, V. | ||||
| Title | Tracking the Origin and Evolution of Plant Metabolites | Type | Journal Article | ||
| Year | 2020 | Publication | Trends in Plant Science | Abbreviated Journal | Trends Plant Sci. |
| Volume | 25 | Issue | 12 | Pages | 1182-1184 |
| Keywords | enzyme evolution; iridoids; Lamiaceae; nepetalactone; plant metabolites | ||||
| Abstract | Iridoids are monoterpenes that are produced by various plants as chemical defense molecules. Lichman et al. recently described the timeline of molecular events that underpin the re-emergence of iridoid biosynthesis in an independent lineage of aromatic plants (catnip). This study represents a benchmark for studying enzyme and metabolite evolution in different clades across the tree of life. © 2020 Elsevier Ltd | ||||
| Address | Biomolécules et Biotechnologies Végétales (BBV) EA 2106, Université de Tours, Tours, France | ||||
| Corporate Author | Thesis | ||||
| Publisher |
Elsevier Ltd | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 13601385 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 937 | ||
| Permanent link to this record | |||||
| Author | Croft, H.; Chen, J.M.; Wang, R.; Mo, G.; Luo, S.; Luo, X.; He, L.; Gonsamo, A.; Arabian, J.; Zhang, Y.; Simic-Milas, A.; Noland, T.L.; He, Y.; Homolová, L.; Malenovský, Z.; Yi, Q.; Beringer, J.; Amiri, R.; Hutley, L.; Arellano, P.; Stahl, C.; Bonal, D. | ||||
| Title | The global distribution of leaf chlorophyll content | Type | Journal Article | ||
| Year | 2020 | Publication | Remote Sensing of Environment | Abbreviated Journal | Remote Sens. Environ. |
| Volume | 236 | Issue | 111479 | Pages | |
| Keywords | |||||
| Abstract | Leaf chlorophyll is central to the exchange of carbon, water and energy between the biosphere and the atmosphere, and to the functioning of terrestrial ecosystems. This paper presents the first spatially-continuous view of terrestrial leaf chlorophyll content (ChlLeaf) at the global scale. Weekly maps of ChlLeaf were produced from ENVISAT MERIS full resolution (300 m) satellite data using a two-stage physically-based radiative transfer modelling approach. Firstly, leaf-level reflectance was derived from top-of-canopy satellite reflectance observations using 4-Scale and SAIL canopy radiative transfer models for woody and non-woody vegetation, respectively. Secondly, the modelled leaf-level reflectance was input into the PROSPECT leaf-level radiative transfer model to derive ChlLeaf. The ChlLeaf retrieval algorithm was validated using measured ChlLeaf data from 248 sample measurements at 28 field locations, and covering six plant functional types (PFTs). Modelled results show strong relationships with field measurements, particularly for deciduous broadleaf forests (R2 = 0.67; RMSE = 9.25 microg cm-2; p < 0.001), croplands (R2 = 0.41; RMSE = 13.18 microg cm-2; p < 0.001) and evergreen needleleaf forests (R2 = 0.47; RMSE = 10.63 microg cm-2; p < 0.001). When the modelled results from all PFTs were considered together, the overall relationship with measured ChlLeaf remained good (R2 = 0.47, RMSE = 10.79 microg cm-2; p < 0.001). This result is an improvement on the relationship between measured ChlLeaf and a commonly used chlorophyll-sensitive spectral vegetation index; the MERIS Terrestrial Chlorophyll Index (MTCI; R2 = 0.27, p < 0.001). The global maps show large temporal and spatial variability in ChlLeaf, with evergreen broadleaf forests presenting the highest leaf chlorophyll values, with global annual median values of 54.4 microg cm-2. Distinct seasonal ChlLeaf phenologies are also visible, particularly in deciduous plant forms, associated with budburst and crop growth, and leaf senescence. It is anticipated that this global ChlLeaf product will make an important step towards the explicit consideration of leaf-level biochemistry in terrestrial water, energy and carbon cycle modelling. | ||||
| Address | UMR EEF, INRA Université de Lorraine, Champenoux54280, France | ||||
| Corporate Author | Thesis | ||||
| Publisher |
Elsevier Inc. | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 00344257 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 898 | ||
| Permanent link to this record | |||||
| Author | Dessert, C.; Clergue, C.; Rousteau, A.; Crispi, O.; Benedetti, M.F. | ||||
| Title | Atmospheric contribution to cations cycling in highly weathered catchment, Guadeloupe (Lesser Antilles) | Type | Journal Article | ||
| Year | 2020 | Publication | Chemical Geology | Abbreviated Journal | Chem. Geol. |
| Volume | 531 | Issue | 119354 | Pages | |
| Keywords | Atmospheric deposit; Cation-nutrient recycling; Critical Zone; Saharan dust; Sr and Nd isotopes; Atmospheric chemistry; Biogeochemistry; Catchments; Deposits; Dust; Ecosystems; Forestry; Isotopes; Lakes; Positive ions; Rain; Recycling; Runoff; Soil moisture; Soil surveys; Tropics; Vegetation; Volcanoes; Weathering; Atmospheric deposits; Critical zones; Nutrient recycling; Saharan dust; Sr and Nd isotopes; Nutrients; catchment; cation; dust; isotopic composition; neodymium isotope; regolith; strontium isotope; trace element; water chemistry; water quality; Guadeloupe; Leeward Islands [Lesser Antilles]; Sahara | ||||
| Abstract | The important fertilizing role of atmospheric dust, and particularly African dust, in tropical rainforests is increasingly recognized but still poorly quantified. To better evaluate dust input into the Caribbean basin, we sampled critical zone compartments of a small forested volcanic catchment in Guadeloupe (soils, parent rock, atmospheric dust, plants, soil solutions, stream and rain waters). The aims of this study are to track sources of cation nutrients (Ca, Mg, K, Sr) developed on highly weathered soil in the rainforest of Guadeloupe, to quantify plant recycling of these nutrients, and to identify constraints on regolith development and its associated nutrient pool. In the Quiock Creek catchment, a large isotopic range of 87Sr/86Sr and eNd values was observed despite the small scale of observation. Sr isotopic composition of the dissolved load varied from 0.7084 in rainfall to 0.7110 in soil solution, whereas it ranges between 0.7068 and 0.7153 for soil samples and between 0.7096 and 0.7102 for plants. The Nd isotopic composition varied between -8.39 in near-surface soil samples to 2.71 in deeper soil. All samples had an intermediate signature between that of the bedrock endmember (87Sr/86Sr = 0.7038; eNd = 4.8) and the atmospheric endmember (sea salt: 87Sr/86Sr = 0.7092 and Saharan dust: 87Sr/86Sr = 0.7187, eNd=-11.5). The regolith was built on pyroclastic deposits, but, because of extreme leaching, the regolith has lost its original bedrock signature and inherited an exogenous atmospheric signature. Our results show that only the chemical weathering of the fresh near-surface minerals can provide nutrients to the ecosystem (first 30 cm). However, this dust weathering is too low to sustain the tropical forest ecosystem on its own. The cationic mass balance at the catchment scale, as well as the Sr isotopic signature, show that cation and Sr fluxes are of atmospheric origin only and that original bedrock no longer participates in nutrient cycles. The vegetation reflects the 87Sr/86Sr of the dissolved pool of atmospheric Sr. At the soil-plant scale, the cation-nutrient fluxes provided by vegetation (litter fall + leaf excretion) are major compared to input and output fluxes. The annual Ca, K, Sr and Mg fluxes within the vegetation are, respectively, 31, 28, 20 and 3 times greater than the exported fluxes at the outlet of the basin. The residence time of nutrients in the vegetation is 16 years for K and close to 45 years for Sr, Ca and Mg. These results emphasize the highly efficient vegetative turnover that dominates the nutrient cycle in the Quiock Creek catchment. This first characterization of biogeochemical cycles in the Guadeloupean rainforest suggests that the forest community of Quiock Creek is sustained by a small near-surface nutrient pool disconnected from the deep volcanic bedrock. We also demonstrated that, even with efficient nutrient recycling, Saharan dust plays a significant role in maintaining ecosystem productivity in Guadeloupe over long-time scales. | ||||
| Address | Laboratoire de biologie et de physiologie végétales, UMR EcoFoG, CNRS, Cirad, INRA, Université des Antilles, Université de Guyane, Pointe-à-Pitre, 97159, France | ||||
| Corporate Author | Thesis | ||||
| Publisher |
Elsevier B.V. | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 00092541 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Export Date: 18 November 2019; Correspondence Address: Dessert, C.; Université de Paris, Institut de physique du globe de Paris, CNRSFrance; email: dessert@ipgp.fr | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 895 | ||
| Permanent link to this record | |||||